KR20200056040A - Ejector for dual purge system of vehicle - Google Patents

Abstract

The present invention relates to an ejector for a dual-purge system of a vehicle. A main objective of the present invention is to provide an improved ejector for a dual-purge system of a vehicle which can facilitate manufacture and reduce costs by a simple configuration in comparison to a conventional ejector, reduce the loss of energy and pressure of a fluid passing therethrough, and effectively mix and discharge fluids. To achieve the objective, the ejector for a dual-purge system of a vehicle comprises: a first pipe unit having a driving inlet as an internal flow path to allow a driving fluid to flow thereinto, and a nozzle unit of a shape with a reduced flow path cross section; a second pipe unit having a suction inlet as an internal flow path to allow a suction fluid to flow thereinto; and a third pipe unit allowing an outlet of the nozzle unit of the first pipe unit and an outlet unit of the second pipe unit to be connected to an inlet thereof, and having an outlet as an internal flow path to discharge the driving fluid and the suction fluid after the driving fluid and the suction fluid are mixed. While the nozzle unit of the first pipe unit and the outlet unit of the second pipe unit are arranged side by side, the nozzle unit of the first pipe unit and the outlet unit of the second pipe unit are connected to the inlet of the third pipe unit to allow the driving fluid passing through the nozzle unit of the first pipe unit and the suction fluid passing through the outlet unit of the second pipe unit to flow into the inlet of the third pipe unit in a direction parallel with the outlet which is the internal flow path of the third pipe unit to merge.

Description

Ejector for dual purge system of vehicle

The present invention relates to an ejector for a dual purge system of a vehicle, and more specifically, compared to a conventional ejector, the configuration is simple, so that it is easy to manufacture and cost reduction is possible, and the pressure and energy loss of the fluid passing through the interior is reduced. The present invention relates to an ejector for an improved vehicle dual purge system capable of smoothly mixing and discharging fluid.

In general, fuel evaporation gas containing fuel components such as gas (e.g., hydrocarbon (HC)) in which fuel evaporates due to various factors occurs in a fuel tank of a vehicle. It pollutes the atmosphere.

Therefore, the vehicle is equipped with an evaporation gas control device for burning fuel evaporation gas in an engine to prevent air pollution, and the evaporation gas control device canister that collects and stores the evaporation gas from the fuel tank. It includes.

In the vehicle, the fuel evaporation gas in the fuel tank enters and accumulates into the canister together with the air that has passed through the air filter, and when the purge control solenoid valve (hereinafter referred to as 'PCSV') is opened by the control signal of the controller, , The fuel component of the fuel evaporation gas accumulated in the canister is sucked into a surge tank, which is an engine intake system, and directed to the combustion chamber.

The canister is configured by filling the case with an adsorbent material capable of adsorbing the fuel component of the fuel evaporation gas moved from the fuel tank, and activated carbon is widely used as the adsorbent material.

Activated carbon functions to adsorb hydrocarbons (HC), which is a fuel component, from the fuel evaporation gas introduced into the case of the canister.

Such a canister adsorbs the fuel component to the adsorbent material when the engine is stopped, and when the engine is run, the fuel component adsorbed to the adsorbent material is driven by the pressure of the air sucked from the outside (atmosphere). Desorption, the desorption of the fuel component is supplied to the engine intake with air.

The operation of inhaling the fuel components collected by the canister into the engine through the purge line is called a purge operation, and the gas drawn from the canister into the engine is called purge gas, and the purge gas is hydrocarbon desorbed from the adsorbent material of the canister. It can be said to be a gas in which fuel components and air are mixed.

In addition, a PCSV for controlling purge operation is installed in the purge line connecting the purge port of the canister and the engine intake, and this PCSV is a valve that is opened during purge operation during engine operation, and uses the fuel components collected by the canister. It is purged from the engine by purging it to the engine intake through the open PCSV with air.

PCSV is a valve controlled by a control unit, for example, an engine control unit (ECU), and opens or closes PCSV (turns on / off purge operation) according to the vehicle driving state for fuel evaporation gas control. Regulating control is performed.

To explain the configuration of a typical canister, the canister includes a case filled with an adsorbent material (eg, activated carbon), which is connected through an engine intake system and a purge line to a purge port that sends fuel components and air to the engine side. , Connected to the fuel tank, a loading port through which fuel evaporation gas flows in, and an air filter (that is, a canister filter) are connected to form an atmospheric port through which air in the air is sucked.

In addition, a partition wall partitioning the space where the standby port is located and the space where the purge port and the loading port are located are formed in the interior space of the case, and the fuel evaporation gas introduced from the fuel tank through the loading port is formed. The fuel component such as hydrocarbon is adsorbed on the adsorbent material while passing through the inner space partitioned by the partition wall.

In addition, when the PCSV is opened by the control unit while the engine is running, and the suction pressure, that is, the engine negative pressure is applied to the inner space of the canister from the engine intake system through the purge port, air is sucked through the air filter and the atmospheric port, and purge Fuel components desorbed by air are discharged from the adsorbent material through the port and sucked into the engine.

For the purge operation to allow air in the air to be sucked into the canister and to remove fuel components such as hydrocarbons from the adsorbent material in the canister by the sucked air, the engine negative pressure is supplied through the purge line and the purge port. It must be allowed to work within the canister.

However, in vehicles equipped with a turbocharged engine, the negative pressure of the engine intake system, such as the intake manifold, is relatively low, or when the turbocharger is operated, a positive pressure is formed in the engine intake system rather than the negative pressure, so it is difficult to purge the canister. .

In particular, in recent years, in response to the trend of engine downsizing, the use of a gasoline direct injection (GDI) engine equipped with a turbocharger for improving fuel efficiency and output, for example, a turbo GDI engine, is increasing.

In the case of the turbo GDI engine, since the static pressure is formed in the intake manifold when the turbocharger is operated (that is, when it is supercharged), it is not possible to use the existing single purge system because the intake manifold does not inhale the purge gas due to the negative pressure. (dual purge) system should be used.

Normally, purging is performed depending on the driving conditions of the engine (for example, purging is not performed for reasons of combustion stability when the engine is idle), and purging is mainly performed using negative pressure on the intake side, so sufficient for the intake side Whether purging is possible depends on whether a negative pressure is formed.

If sufficient negative pressure is formed on the intake side, it is necessary to purge as often as possible to remove the fuel component in the canister.

However, in the case of a turbocharged engine (that is, a supercharged engine), there is a limitation in the driving area capable of performing a purge function due to the turbocharger operation (supercharged). There are more restrictions on when and when the loaded fuel components can be purged.

To compensate for this, in the turbocharged engine, a dual purge system is widely used in place of the existing single purge system. In this dual purge system, when the turbocharger is operated, a forced negative pressure is generated through an ejector, whereby the position before supercharging, that is, compression The purge gas is sucked into the compressor before the position.

1 is a view illustrating a conventional ejector used in a dual purge system, and FIG. 2 is a cross-sectional view illustrating a conventional ejector, as shown, the conventional ejector 40 is a 3-pipe (pipe) combination Or a combination of a 3-pipe and a 1-chamber, a drive inlet 41 through which drive fluid flows into each pipe side, and a suction inlet 42 through which suction fluid (purge gas) flows in. , The outlet 43 is discharged after the driving fluid and the suction fluid are mixed.

This conventional ejector has the disadvantages of a complicated configuration, difficult to manufacture, and high cost.

For example, in a conventional ejector, in addition to a configuration in which three pipes are combined, a separate nozzle 44 through which a driving fluid passes is installed or a purge line (reference numeral '33' in FIGS. 3 and 4). ) May be provided with a separate inner space chamber 45 on the side of the suction inlet 42 to which it is connected.

In addition, in the conventional ejector, as can be seen in FIG. 2, the suction fluid (purge gas) introduced through the suction inlet 42 flows through the driving inlet 41 and passes through the interior of the ejector 40 in a substantially perpendicular direction. It is supposed to meet.

2, the flow cross-sectional area in the ejector 40 when the driving fluid entering the drive inlet 41 of the ejector 40 through the recirculating fluid line 37 moves substantially horizontally from left to right in the drawing. In this reduced portion, the speed of the driving fluid is rapidly increased and the pressure is lowered, but the driving fluid has a moment of inertia energy inside the ejector 40 to a certain degree, and is substantially straight from the left to the right in the drawing. It will move horizontally in the form of a flow.

At this time, in the conventional ejector, the purge gas sucked through the suction inlet 42 with respect to the driving fluid exhibiting a straight flow therein collides in a substantially right angle direction, and thus, pressure and energy loss of the fluid may occur due to the collision. Can be.

In addition, after that, the two fluids must be well mixed and then smoothly discharged through the outlet 43 of the ejector 40, but there is a problem that fluid flow is not smooth in mixing and discharging the two fluids.

Accordingly, the present invention has been created to solve the above problems, and has an object to provide an ejector for a dual purge system of a vehicle that is simple in construction, easy to manufacture, and capable of cost reduction compared to a conventional ejector.

In addition, another object of the present invention is to provide an improved ejector capable of reducing pressure and energy loss of a fluid passing through the interior, and smoothly mixing and discharging fluid.

In order to achieve the above object, according to an aspect of the present invention, a drive pipe inlet with a driving fluid flowing as an internal flow path, and a first pipe portion formed with a nozzle portion having a reduced flow path cross-sectional area; A second pipe portion formed with an inlet through which suction liquid flows as an internal flow path; And a third pipe portion in which an outlet portion of the nozzle portion of the first pipe portion and an outlet portion of the second pipe portion are connected to the inlet, and an outlet through which the driving fluid and the suction fluid are mixed and discharged as an internal flow path is formed, and wherein the outlet portion is formed. The driving fluid passing through the nozzle part of the first pipe part and the suction fluid passing through the outlet part of the second pipe part are connected to the inlet of the third pipe part in a state where the outlet parts of the nozzle part and the second pipe part are arranged side by side. It provides an ejector for a dual purge system of a vehicle, characterized in that it flows in and out in a parallel direction to the outlet, which is the internal flow path of the negative.

In addition, in a preferred embodiment of the present invention, the first pipe portion and the third pipe portion are disposed to extend in a straight line, and the second pipe portion is disposed to be elongated in a direction perpendicular to the first pipe portion and the third pipe portion. Can be.

In addition, in a preferred embodiment of the present invention, the bottom portion of the first pipe portion is formed in a shape that gradually rises upward while forming a curve from one side, and is connected to the nozzle portion, and the cross-sectional area of the flow path of the drive inlet, which is the inner flow path of the first pipe portion, is It may be a structure that is gradually reduced to the nozzle portion by the shape of the bottom portion.

In addition, in a preferred embodiment of the present invention, the nozzle portion may have a structure in which the cross-sectional area of the flow passage gradually decreases as the cross-sectional area of the flow passage goes toward the inlet of the third pipe portion.

In addition, in a preferred embodiment of the present invention, the nozzle portion may have a structure in which the cross-sectional area of the flow path gradually decreases and then enlarges again as the flow path cross-sectional area goes toward the inlet of the third pipe portion.

In addition, in a preferred embodiment of the present invention, the second pipe portion has a curved portion bent at an end connected to the third pipe portion, and an outlet portion of a predetermined length formed to extend behind the curved portion is formed in a straight shape. It may be connected to the inlet of the third pipe portion.

Thus, according to the ejector for a dual purge system of a vehicle according to the present invention, there is an advantage in that the configuration is simple, easy to manufacture, and can reduce cost compared to a conventional ejector.

In addition, the ejector according to the present invention can reduce the pressure and energy loss of the fluid passing through the interior, there is an advantage that can be smoothly mixed and discharged fluid.

1 is a front view illustrating an ejector for a conventional dual purge system.
2 is a cross-sectional view illustrating a conventional dual purge system ejector.
3 and 4 are schematic diagrams showing the configuration of a turbocharged engine to which a known dual purge system is applied.
5 to 9 is a view showing an ejector according to an embodiment of the present invention.
10 is a view showing Example 1 of the present invention.
11 is a view showing a second embodiment of the present invention.
12 is a view of a comparative example according to the prior art, showing a shape of a comparative example for performance analysis.
13 is a view showing the results of the internal flow analysis of Example 1 and Example 2 of the present invention.
14 is a view showing the performance analysis results of Example 1 and Example 2 according to the present invention and Comparative Example 2 according to the prior art.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms.

Throughout the specification, when a part “includes” a certain component, this means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

First, in order to help the understanding of the present invention will be described in more detail with respect to the known dual purge system as follows.

3 and 4, the air cleaner 11, the intake pipe 12, the compressor 13 of the turbocharger for sucking and compressing air, and the intercooler for cooling the air compressed by the compressor 13 ( 14) is shown.

Also shown is an engine 10 that includes a throttle valve 15, a surge tank 16, an intake manifold 17, a cylinder head and block 18, and the like.

The air drawn by the compressor 13 of the turbocharger flows along the intake pipe 12 in the air cleaner 11, while the compressor 13, the intercooler 14, the throttle valve 15, the surge tank 16, It is supplied to the combustion chamber of the engine 10 via the intake manifold 17.

In addition, the fuel tank 21 in which fuel is stored, the canister 22 for collecting the fuel evaporation gas generated in the fuel tank 21, and the fuel components of the fuel evaporation gas collected in the canister 22 are supplied to the engine for combustion The configuration of the dual purge system 30 is shown.

Here, the canister 22 is provided with a purge port 23, a loading port 24, a standby port 25, and a partition wall 26 is provided inside the canister 22.

3 and 4, reference numeral '27' denotes an air filter.

In addition, the dual purge system 30 includes a main purge line 31 connected to the purge port 23 of the canister 22, and a first purge line 32 branched from the main purge line 31 and connected to the engine intake system 32 ), The second purge line 33 branched from the main purge line 31, the PCSV 34 installed in the main purge line 31 to control the purge operation, the first purge line 32 and the 2 Check valves 35 and 36 respectively installed in the purge lines 33, the second purge lines 33 are connected, and are directly connected to the intake pipe 12 at the front end of the compressor 13 or a separate conduit 38 ) May include an ejector 40 connected through a throttle valve 15 and a recirculation flow line (RFL) 37 that connects between the intake pipe 12 and the ejector 40 at a front end position. .

Here, the main purge line 31, the first purge line 32 and the second purge line 33, the conduit 38 constitutes a purge line for flowing the purge gas to the intake pipe 12, this Among them, the first purge line 32 may be branched from the main purge line 31 and connected to the intake pipe 12 at a rear end position of the throttle valve 15 during engine intake.

In the illustrated dual system, according to the pressure state of the surge tank 16, after the mixed gas of the fuel component and air sucked from the canister 22 passes through the open PCSV 34, the first purge line 32 ) Through the engine intake system, or the second purge line 33 and the ejector 40, the intake pipe 12 at the front end of the compressor 13, the compressor 13, the intake pipe 12 at the rear end position , After passing through the intercooler 14, is sucked into the surge tank 16 through the throttle valve 15.

The ejector 40 is a device for forcibly forming a negative pressure during the operation of the turbocharger, the recirculating fluid line 37 is connected to the driving inlet 41 through which the driving fluid flows, and the suction fluid (purge gas) is sucked The second purge line 33 is connected to the inlet 42.

In addition, the outlet (for example, the outlet of the diffuser) 43, which is discharged in a state in which the driving fluid and the intake fluid are mixed, is directly connected to the intake pipe 12 at the front end of the compressor 13 or the conduit 38 Is connected through.

Accordingly, the recirculation fluid line 37 becomes a conduit connecting the intake pipe 12 and the ejector 40 at the front end of the throttle valve 15, and the compressor 13 rotates when the turbocharger is operated (supercharged). When compressing the air sucked through the air cleaner 11, air (driving fluid) flows into the ejector 40 from the intake pipe 12 located at the rear end of the compressor 13 through the recirculating fluid line 37, A negative pressure is generated while the incoming air passes through the ejector 40.

When the negative pressure at this time acts on the canister 22 through the second purge line 33, the main purge line 31, and the open PCSV 34, the purge gas in which air and fuel components are mixed from the canister 22 ( After the intake fluid) is sucked, and finally the sucked purge gas is sucked through the recirculating fluid line 37 into the intake pipe 12 at the front end position of the compressor 13 in a mixed state with the sucked air (driving fluid), It is supplied to the combustion chamber of the engine along the path of the compressor 13, the intercooler 14, the throttle valve 15, the surge tank 16, and the intake manifold 17 along the intake pipe 12.

The single purge system is a system without the second purge line 33 and the ejector 40. In the PCSV 34 open state, the purge gas draws the purge line from the canister 22 only by the negative pressure of the engine (negative pressure of the surge tank). After being sucked through the engine, it is burned in the combustion chamber of the engine.

On the other hand, the dual purge system 30 is a system that enables purging even when a static pressure is formed in the surge tank 16 and the intake manifold 17 due to the inflow of compressed air during operation of the turbocharger, such a dual purge system 30 In), the second purge line 33 and the ejector 40 are additionally installed as the turbocharger is installed as described above.

Accordingly, in the dual purge system 30, when negative pressure is generated in the surge tank 16 of the engine, the purge gas from the canister 22 is sucked through the main purge line 31 and the first purge line 32 and supplied to the engine. Although it can be, when the static pressure is formed in the engine by the operation of the turbocharger, the purge gas is sucked into the ejector 40 through the main purge line 31 and the second purge line 33 and then the intake pipe 12 Accordingly, it is supplied to the combustion chamber of the engine.

The present invention relates to an ejector 40 that can be used in the vehicle's dual purge system 30, and the configuration of the dual purge system 30 in which the ejector 40 can be used in the following description is shown in FIGS. 3 and 4 See.

5 to 9 is a view showing an ejector according to an embodiment of the present invention, Figure 5 is a front view of the ejector according to an embodiment of the present invention, Figure 6 is a bottom view of the ejector according to an embodiment of the present invention , FIG. 7 is a plan view of the ejector, and FIGS. 8 and 9 are perspective views of the ejector.

In the other configurations of the dual purge system 30 in which the ejector 40 can be used, except for the ejector 40 according to the embodiment of the present invention, there is no difference compared to the known dual purge system, and thus the ejector ( Other configurations of the dual purge system 30 except for 40) have been sufficiently described above, and thus detailed description will be omitted.

Ejector 40 illustrated in the drawings as an embodiment of the present invention is a device forcibly generating a negative pressure for purge operation when a turbocharger is operated in a dual purge system 30, with a pipe 46 having a predetermined thickness It can be configured, and the internal passage of the pipe 46 becomes the flow path of the fluid.

Ejector 40 according to an embodiment of the present invention may have an approximately 'T'-shaped in the overall shape, the drive is a flow path through which the driving fluid flows on one side of the pipe 46 forming a' T'-shaped The inlet 41 is formed, and the suction inlet 42 which is a flow path through which the suction fluid (purge gas) flows is formed on the other side of the pipe 46.

In addition, on the other side of the pipe 46 forming the 'T' shape, an outlet 43, which is a flow path discharged after the driving fluid and the suction fluid are mixed, is formed.

In the vehicle's dual purge system 30, a recirculation fluid line 37 is connected to the drive inlet 41 of the ejector 40, and a second purge line 33 is connected to the suction inlet 42 of the ejector 40. The outlet 43 of the ejector 40 is directly connected to the intake pipe 12 at the front end position of the compressor 13 or connected through a separate pipe 38.

And, in the ejector 40 according to the embodiment of the present invention, the pipe 46 is a first pipe portion 47a on which a driving inlet 41 through which a driving fluid flows is formed, and a suction inlet 42 through which suction fluid is sucked The formed second pipe portion 47b may include a third pipe portion 47c having an outlet 43 through which a driving fluid and a suction fluid are mixed.

In an embodiment of the present invention, the first pipe portion 47a, the second pipe portion 47b, and the third pipe portion 47c are disposed to form a 'T' shape and are integrally connected, wherein the first pipe portion ( 47a) and the third pipe portion 47c may be arranged to form a straight line.

In addition, in the embodiment of the present invention, the second pipe portion 47b may be positioned to be disposed to be elongated in a direction substantially perpendicular to the first pipe portion 47a and the third pipe portion 47c, wherein the first pipe portion The second pipe portion 47b may be combined and connected to a portion where the portion 47a and the third pipe portion 47c are connected.

Referring to FIG. 5, the first pipe portion 47a is located on the left side, and the third pipe portion 47c is located on the right side, wherein the first pipe portion 47a and the third pipe portion 47c are shown in the drawing. It can be seen that they are arranged horizontally while forming a straight line from side to side.

In addition, the first pipe portion 47a through which the driving fluid flows has a structure in which a cross-sectional area is gradually reduced as the pipe portion itself goes toward the third pipe portion 47c, and as shown in FIG. 5, in the longitudinal direction With respect to the first pipe portion (47a) from the approximately middle portion of the bottom portion of the first pipe portion (47a) may have a structure that forms a gentle curve gradually increasing upward.

That is, the first pipe portion 47a is formed so that the entire portion in the longitudinal direction does not have a straight pipe shape having the same diameter, but the bottom portion 48a gradually rises upward from the middle portion. It is done.

As a result, the first pipe portion 47a has a structure in which the cross-sectional area of the flow path, which is the inner passage of the first pipe portion 47a, gradually decreases from an approximately middle portion where the bottom portion 48a starts to rise upward.

In addition, the end portion of the first pipe portion 47a where the flow path cross-sectional area is gradually reduced, that is, the end connected to the third pipe portion 47c is a nozzle portion 48b having a smaller flow path cross-sectional area than other portions.

After all, the drive inlet 41, which is the inner flow path of the first pipe portion 47a, has a gentle curve, and gradually has a structure in which the cross-sectional area of the flow path is gradually reduced by the shape of the bottom surface portion 48a that rises upward, and the bottom surface. While the portion 48a is connected to the nozzle portion 48b, the flow path cross-sectional area of the drive inlet 41 which is the internal flow path continues to be reduced to the outlet portion of the nozzle portion 48b connected to the inlet of the third pipe portion 47c. Becomes.

In addition, the second pipe portion 47b has a curved portion 49 of a curved shape, such as a curved pipe at an end connected to the third pipe portion 47c, and the curved portion ( 49) The rear outlet portion 49a extends linearly by a predetermined length and is connected to the inlet of the third pipe portion 47c.

At this time, the outlet of the nozzle portion of the first pipe portion 47a is connected to the inlet of the third pipe portion 47c, and the outlet portion 49a of the second pipe portion 47b is also connected to the third pipe portion 47c. It leads to the entrance.

Referring to FIG. 5, the outlet portion 49a of the first pipe portion 47a, which is in a straight line with the third pipe portion 47c in the second pipe portion 47b, has a nozzle portion 48b of the first pipe portion 47a. It can be seen that it is located on the lower side, and it can be seen that the outlet portion 49a is disposed in a direction substantially parallel to the nozzle portion 48b of the first pipe portion 47a.

And, when looking at the ejector 40 from the bottom as shown in Figure 6, or looking down from above, as shown in Figure 7, the first pipe portion 47a gradually decreases the outer diameter and inner diameter of the pipe from one side of the portion where the cross-sectional area of the flow path is gradually reduced. The outer diameter is constant in at least a portion of the nozzle portion 48b of the first pipe portion 47a connected to the third pipe portion 47c.

Further, in the nozzle portion 48b of the first pipe portion 47a, the outer diameter and inner diameter are smaller than the outer diameter and inner diameter of the second pipe portion 47b.

Accordingly, the nozzle portion 48b of the first pipe portion 47a has a shape in which the flow path cross-sectional area is gradually reduced, and the flow path cross-sectional area is reduced in the nozzle portion 48b of the first pipe portion 47a and then the nozzle portion 48b Since the flow path cross-sectional area suddenly increases again in the third pipe portion 47c after passing through the outlet of), the nozzle portion 48b becomes a throat portion that maintains a small state before the flow path cross-sectional area increases.

FIG. 10 is a view showing a first embodiment of the present invention, and FIG. 11 is a view showing a second embodiment of the present invention, in which the flow path cross-sectional area of the nozzle portion 48b is a third pipe portion 47c. An embodiment having a nozzle-reducing structure that gradually decreases as it goes toward the direction, and in the second embodiment, the nozzle cross section of the flow path of the nozzle portion 48b decreases to the third pipe portion 47c and decreases in minimum cross-sectional area and then gradually expands again. It is an embodiment having an augmented structure.

As described above, in the ejector (Example 1) having a nozzle-reducing structure in which the flow path cross-sectional area is gradually reduced in the nozzle portion 48b of the first pipe portion 47a, and in the nozzle portion 48b of the first pipe portion 47a An ejector (Example 2) having a nozzle-enhancement structure in which the flow path cross-sectional area is reduced and then expanded again may be configured.

On the other hand, the increase in the flow rate of the driving fluid flowing into the ejector 40 through the driving inlet 41 of the first pipe portion 47a is the inside of the ejector 40 through the recirculation fluid line 37 from the engine intake system. It means that the flow rate of the air flowing into the air is increased.

In addition, since the air flowing into the ejector 40 through the recirculation fluid line 37 is a part of the air supplied to the combustion chamber of the engine, it is an engine that increases the flow rate of air flowing into the ejector 40 as a driving fluid. It means that the flow rate of air supplied to the combustion chamber is reduced.

This applies not only to the case of the dual purge system and its engine using a known ejector, but also to the case of using the ejector 40 of the present invention.

Accordingly, when the flow rate of the air, which is the driving fluid in the ejector 40 increases, the flow rate of fresh air supplied to the combustion chamber of the engine through the intake manifold 17 decreases, which decreases engine performance soon. Can cause.

Therefore, an ejector capable of inhaling a large flow rate of the suction fluid even with a low flow rate of the driving fluid can be regarded as an ejector of excellent specifications.

In more detail, when the flow rate ratio ω is defined as '(the flow rate of the suction fluid) / (the flow rate of the driving fluid)', the larger the flow rate ratio, the more the flow rate is the suction fluid even if the same flow rate driving fluid is used. Means an ejector that can inhale.

Likewise, the larger the flow rate ratio, the larger the flow rate means that the ejector uses less flow of the driving fluid when the suction fluid of the same flow rate is sucked.

Therefore, a higher flow rate ratio means that the ejector is superior in performance to suck the purge gas.

Compared from the viewpoint of such a flow rate ratio, the ejectors of the present invention, such as those of the first and second embodiments, exhibit excellent performance compared to the conventional ejectors.

The present inventors performed flow analysis and performance analysis on the ejectors of Examples 1 and 2 and the ejectors of Comparative Examples, and from the results, the ejectors of Examples 1 and 2 of the present invention were compared to the conventional ejectors of Comparative Examples. In comparison, it was confirmed that the ejector performance in terms of the flow rate ratio as well as the fluid flow characteristics in the ejector was better.

In more detail, internal flow analysis of Examples 1 and 2, and Comparative Examples was performed using a flow analysis program on a computer. In this case, ejector shapes of Examples 1, 2, and Comparative Examples are respectively shown. 10, as shown in FIG. 11, FIG.

That is, Example 1 is a nozzle reduction type ejector of the shape shown in FIG. 10 as described above, Example 2 is a nozzle enlargement type ejector of the shape shown in FIG. 11, and the comparative example is shown in FIGS. It is an ejector of the shape shown in FIG.

12 shows the shape of the internal flow path (flow core shape) in the ejector of the comparative example, the 'A' part represents an orifice part for PCSV simulation, and the 'B' part is an outlet part of a boosting nozzle in the ejector. The inner diameter of the outlet portion of this boosting nozzle was set to 1.0 to 1.7 mm.

In addition, as an analysis condition, the same value was applied to the interface of the single product for both the ejectors of Example 1 and Example 2 and Comparative Example, and the boosting side inlet pressure, that is, the boosting pressure (P_rel) [mbar] was 250 to It was set in the range of 2200 mbar.

The boosting side means the turbocharger rear end side, that is, the engine intake side, to which the first pipe part 47a of the ejector 40 is connected through the recirculation fluid line 37, where the engine intake system is the turbocharger rear end position (ie It means the section of the intake pipe 12, which is the rear end of the compressor 13 and the rear end of the intercooler 14) and the front end of the throttle valve 15.

In addition, the boosting-side inlet means a portion of the drive inlet 41 that is a flow path portion in the first pipe portion 47a of the ejector 40, and the boosting-side inlet pressure means pressure in the drive inlet 41, hereinafter In the description of, the inlet pressure on the boosting side will be abbreviated as boosting pressure.

In addition, the PCSV side inlet pressure and the turbocharger front side outlet pressure (P_abs) were set to 1 bar.

Here, the PCSV side inlet is a flow path portion in the second pipe portion 47b of the ejector 40 connected to the PCSV 34 side through a purge line (second purge line 33 and main purge line 31). The suction inlet 42 means a portion, and the PCSV side inlet pressure means the pressure in the suction inlet 42.

In addition, the front end of the turbocharger means a portion of the outlet 43, which is a flow path part in the third pipe portion 47c of the ejector 40, and the front end pressure of the turbocharger means the pressure at the outlet 43. .

The front end of the turbocharger means a section of the intake pipe 12 at the front end of the compressor 13 to which the third pipe portion 47c and the outlet 43 of the ejector 40 are connected.

Looking at the analysis results, Figure 13 is a view showing the results of the internal flow analysis of Example 1 and Example 2 of the present invention, Figure 14 is Example 1 and Example 2 according to the present invention and a comparative example according to the prior art Fig. 2 shows the results of performance analysis.

Referring to FIG. 13, the flow rate of the driving fluid is relatively low in the drive inlet 41 portion, which is the flow path portion in the first pipe portion 47a, in both the ejectors of Example 1 and Example 2, but the nozzle portion ( It can be seen that the flow velocity at 48b) is highest at both ejectors 40.

In addition, while the driving fluid passes through the nozzle portion 48b at a high speed, the suction fluid is sucked through the suction inlet 42 portion, which is a flow path portion in the second pipe portion 47b, so that it is in the third pipe portion 47c. In the outlet portion 43 that is the flow path portion, the suctioned suction fluid is mixed with the driving fluid, and in this case, the suction fluid is mixed with the driving fluid at a relatively high speed, and the suction fluid together with the driving fluid is also the outlet 43 of the ejector 40 You can see it passing quickly.

At this time, in the ejector 40 of the first and second embodiments, the nozzle part 48b, which is the central part of the ejector, exhibits a low pressure state as the fluid flow is accelerated, and the suction inlet 42 part is generated by the low pressure state of the driving fluid. The purge gas, which is the suction fluid of the purge lines 31 and 33, is sucked, so that the purge gas sucked through the second pipe part 47b of the first pipe part 47a and the second pipe part 47b After mixing the internal straight flow path with the driving fluid passing at high speed in a state of inertia, it is discharged to the outside of the ejector 40 through the outlet 43 portion.

In the first and second embodiments, the flow of the driving fluid is greatly accelerated through the nozzle unit 48b, while the pressure of the driving fluid is lowered, and the suction fluid sucked by the driving fluid low pressure state is the second pipe part. After passing through the curved portion 49 at 47b, it flows into the third pipe portion 47c in a direction substantially parallel to the driving fluid.

In particular, the driving fluid and the suction fluid sucked by the driving fluid flow into the third pipe portion 47c in a substantially parallel direction (parallel direction) so that the suction fluid naturally joins and mixes without a great collision with the driving fluid, As a result, the driving fluid and the intake fluid are well mixed without pressure loss and energy loss due to collision, and then can be discharged from the ejector 40.

In this way, the suction fluid and the driving fluid can naturally join without a great collision while the suction fluid flows into the third pipe portion 47c in a direction substantially parallel to the driving fluid (parallel direction), and at this time, the inertial energy of the driving fluid and The flow energy is well transmitted to the intake fluid without any significant loss, so that the intake fluid joining it together with the driving fluid can also be well escaped from the ejector 40 through the outlet 43.

Referring to FIG. 14, it can be seen that in the case of Example 1 and Example 2, the flow rate ratio is greater than that of the comparative example in all ranges of the boosting pressure. It means that it exhibits an overwhelmingly superior performance compared to the conventional comparative example.

In this way, the ejector according to the present invention has a 1-pipe type structure, so the structure is simple and easy to manufacture compared to the conventional ejector having a 3-pipe type structure or a 3-pipe and 1-chamber type structure. And it has the advantage of possible cost reduction.

In addition, the ejector according to the present invention has excellent fluid flow characteristics compared to a conventional ejector, and also has an advantage over a conventional ejector in terms of flow rate ratio ejector performance.

The embodiments of the present invention have been described in detail above, but the scope of rights of the present invention is not limited thereto, and various modifications and improvements of a person skilled in the art using the basic concept of the present invention as defined in the following claims. Also included in the scope of the present invention.

10: engine 11: air cleaner
12: intake pipe 13: compressor
14: intercooler 15: throttle valve
16: Surge tank 17: Intake manifold
18: cylinder head and block 21: fuel tank
22: Canister 23: Purge port
24: loading port 25: standby port
26: bulkhead 27: air filter
30: dual purge system 31: main purge line
32: first purge line 33: second purge line
34: purge control solenoid valve (PCSV) 35, 36: check valve
37: recirculation fluid line 38: pipeline
40: ejector 41: driving inlet
42: suction inlet 43: outlet
44: nozzle 45: chamber
46: pipe 47a: first pipe portion
47b: 2nd pipe part 47c: 3rd pipe part
48a: bottom part 48b: nozzle part
49: curved portion 49a: outlet portion

Claims (10)

A driving pipe through which a driving fluid flows as an internal flow path, and a first pipe portion in which a nozzle portion having a shape in which the flow path cross-sectional area is reduced is formed;
A second pipe portion formed with an inlet through which suction liquid flows as an internal flow path; And
An outlet portion of the nozzle portion of the first pipe portion and an outlet portion of the second pipe portion are connected to the inlet, and a third pipe portion having an outlet through which the driving fluid and the suction fluid are mixed and discharged as an internal flow path is formed,
The nozzle portion of the first pipe portion and the outlet portion of the second pipe portion are connected to the inlet of the third pipe portion in a state arranged side by side, and the driving fluid passing through the nozzle portion of the first pipe portion and suction passing through the outlet portion of the second pipe portion Ejector for a dual purge system of a vehicle, characterized in that the fluid flows into and flows in a parallel direction to the outlet, which is an internal flow path of the third pipe part.
The method according to claim 1,
The first pipe portion and the third pipe portion are arranged to extend in a straight line,
Ejector for a dual purge system of a vehicle, characterized in that the second pipe portion is disposed in a direction perpendicular to the first pipe portion and the third pipe portion.
The method according to claim 1 or claim 2,
The bottom portion of the first pipe portion is formed in a shape that gradually rises upwards while forming a curve from one side and is connected to the nozzle portion,
Ejector for a dual purge system of a vehicle, characterized in that the flow path cross-sectional area of the drive inlet which is the inner flow path of the first pipe portion is gradually reduced to the nozzle portion by the shape of the bottom portion.
The method according to claim 1 or claim 2,
The nozzle portion ejector for a dual purge system of a vehicle, characterized in that the cross-sectional area of the flow path gradually decreases as the passage cross-section toward the inlet of the third pipe portion.
The method according to claim 1 or claim 2,
The nozzle portion ejector for a dual purge system of a vehicle, characterized in that the cross-sectional area of the passage gradually decreases and then enlarges again as the passage cross-section goes toward the inlet of the third pipe.
The method according to claim 1 or claim 2,
The second pipe portion
It has a curved portion of a curved shape at the end connected to the third pipe portion,
Ejector for a dual purge system of a vehicle, characterized in that the outlet portion of a predetermined length formed to extend behind the curved portion is formed in a straight shape and connected to the inlet of the third pipe portion.
The method according to claim 1,
A recirculation fluid line connected from an engine intake system is connected to the driving inlet of the first pipe part, and an ejector for a dual purge system of a vehicle is characterized in that recirculated air is introduced along the recirculation fluid line from the engine intake system as the driving fluid. .
The method according to claim 7,
The engine intake system is a dual purge system ejector for a vehicle, characterized in that the intake pipe in the rear end position of the compressor of the turbocharger.
The method according to claim 1,
A purge line in which a purge control solenoid valve is installed is connected to the suction inlet of the second pipe part, so that the purge gas is sucked through the purge control solenoid valve from the canister as the suction fluid.
The method according to claim 1,
The injector for a dual purge system of a vehicle, wherein the outlet of the third pipe part discharged after the driving fluid and the intake fluid are mixed is directly connected to an intake pipe at a position in front of a compressor of a turbocharger or through a separate pipe.

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